The present invention relates generally to railroad maintenance machinery, and more specifically to equipment used for handling and replacing rail tie plates during the reconditioning of railroad track.
During conventional railroad track maintenance, spikes are removed and rail plates removed from the ties. The rail is lifted, then the ties are withdrawn. In some cases, the tie plates remain embedded in the ties and must be manually removed. While the rail is lifted, a new tie is inserted beneath the rail. Then, the tie plates are replaced in position between a foot of the rail and an upper surface of the tie. Once the tie is replaced and the tie plate repositioned, fasteners such as spikes are inserted into the tie to secure the tie plate in position. Next, rail anchors are applied as desired at edges of the tie plate.
A suitable tie exchange machine is disclosed in commonly-assigned U.S. Pat. No. 6,463,858 which is incorporated by reference. Also, conventional tie plate placement devices are disclosed in U.S. Pat. No. 7,497,166 and U.S. Pat. No. 6,863,717 also incorporated by reference.
It is desirable for the operations of railroad track reconditioning, and specifically rail tie replacement, to be automated as much as possible. Manual lifting and placement of rail tie plates is laborious. Thus, there is a need for an automated tie plate handling apparatus.